rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P12869/1:b..l rcu: (detected by 1, t=10502 jiffies, g=91909, q=425 ncpus=2) task:syz.0.2221 state:R running task stack:22024 pid:12869 tgid:12869 ppid:5650 task_flags:0x40064c flags:0x00080001 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1821/0x5740 kernel/sched/core.c:7189 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7513 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline] irqentry_exit+0x14f/0x8b0 kernel/entry/common.c:164 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:unwind_next_frame+0xf37/0x2550 arch/x86/kernel/unwind_orc.c:-1 Code: 4c 8b 64 24 18 74 08 48 89 df e8 f4 1f ba 00 4c 89 23 ba 10 00 00 00 48 8b 5c 24 28 48 89 df 31 f6 e8 bd 21 ba 00 48 8b 3c 24 d0 04 00 00 4c 89 64 24 18 4d 8d 6e 08 4d 89 ec 49 c1 ec 03 41 RSP: 0018:ffffc90003326d38 EFLAGS: 00000246 RAX: ffffc90003326eb8 RBX: ffffc90003326eb8 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff90c3724a RBP: dffffc0000000000 R08: ffffc90003326ec7 R09: 0000000000000000 R10: ffffc90003326eb8 R11: fffff52000664dd9 R12: ffffc90003326f00 R13: 1ffff92000664dcf R14: ffffc90003326e68 R15: ffffc90003326eb0 __unwind_start+0x5b8/0x760 arch/x86/kernel/unwind_orc.c:787 unwind_start arch/x86/include/asm/unwind.h:64 [inline] arch_stack_walk+0xe3/0x150 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 save_stack+0x122/0x230 mm/page_owner.c:165 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:320 reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1397 [inline] free_unref_folios+0xd9f/0x14c0 mm/page_alloc.c:2999 folios_put_refs+0x9ff/0xb40 mm/swap.c:1008 folio_batch_release include/linux/folio_batch.h:101 [inline] shmem_undo_range+0x52c/0x1660 mm/shmem.c:1149 shmem_truncate_range mm/shmem.c:1277 [inline] shmem_evict_inode+0x289/0xae0 mm/shmem.c:1407 evict+0x61e/0xb10 fs/inode.c:841 __dentry_kill+0x1a2/0x690 fs/dcache.c:718 finish_dput+0xc9/0x480 fs/dcache.c:927 __fput+0x691/0xa60 fs/file_table.c:518 task_work_run+0x1d9/0x270 kernel/task_work.c:233 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x70f/0x22c0 kernel/exit.c:976 do_group_exit+0x21b/0x2d0 kernel/exit.c:1119 get_signal+0x1284/0x1330 kernel/signal.c:3038 arch_do_signal_or_restart+0xbc/0x840 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline] exit_to_user_mode_loop kernel/entry/common.c:98 [inline] __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:244 [inline] irqentry_exit_to_user_mode include/linux/irq-entry-common.h:315 [inline] irqentry_exit+0x2aa/0x8b0 kernel/entry/common.c:162 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x7fdff3452b27 RSP: 002b:00007fdff43af120 EFLAGS: 00010202 RAX: 0000000000000000 RBX: 000000000000000b RCX: 00007fdff359ce59 RDX: 00007fdff43af140 RSI: 00007fdff43af270 RDI: 000000000000000b RBP: 00007fdff3632d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007fdff3816128 R14: 00007fdff3816090 R15: 00007fdff393fa48 rcu: rcu_preempt kthread starved for 9990 jiffies! g91909 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior. rcu: RCU grace-period kthread stack dump: task:rcu_preempt state:R running task stack:27544 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1821/0x5740 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0x164/0x360 kernel/sched/core.c:7283 schedule_timeout+0x158/0x2c0 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x312/0x11d0 kernel/rcu/tree.c:2095 rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2297 kthread+0x389/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: Stack dump where RCU GP kthread last ran: CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63 Code: bb 7e 02 e9 03 fa 02 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d e3 f1 21 00 fb f4 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 RSP: 0018:ffffc90000197e20 EFLAGS: 00000246 RAX: 0000000000e5c035 RBX: ffffffff819a858a RCX: 0000000080000001 RDX: 0000000000000001 RSI: ffffffff8dfa4dc8 RDI: ffffffff8c28b9e0 RBP: ffffc90000197f10 R08: ffff8880b87339db R09: 1ffff110170e673b R10: dffffc0000000000 R11: ffffed10170e673c R12: 0000000000000001 R13: 1ffff11003b5b000 R14: 0000000000000001 R15: 1ffff11003b5b000 FS: 0000000000000000(0000) GS:ffff8881253a0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f123aa80fdf CR3: 000000002cccc000 CR4: 00000000003526f0 Call Trace: arch_safe_halt arch/x86/kernel/process.c:766 [inline] default_idle+0x9/0x20 arch/x86/kernel/process.c:767 default_idle_call+0x72/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:199 [inline] do_idle+0x36a/0x5f0 kernel/sched/idle.c:352 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:451 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312 common_startup_64+0x13e/0x147